This invention relates to portable toilets and is particularly concerned with a new and improved arrangement for emptying the contents of the holding tank of a portable toilet.
A number of commonly assigned patents disclose portable toilets of the type which comprise a holding tank section and a seat section separably mounted on the holding tank section. The seat section comprises a bowl with a bottom outlet which registers with an opening in the top wall of the holding tank. When the two sections are mounted together the bowl outlet is in sealed relationship with the opening in the top wall of the holding tank. A valve in the holding tank is disposed at the opening and when the valve is operated the contents of the bowl drop into the holding tank. The accumulated contents of the holding tank are dumped from time to time at suitable sanitary disposal stations.
One usual practice has been to provide a threaded boss circumscribing an outlet opening and a threaded cap threaded onto the boss to close the opening. When the contents are to be dumped, the cap is unscrewed and the waste materials poured out. More recent holding tanks have been provided with a rotatably mounted discharge spout to facilitate flow of the tank contents out of the tank. Co-pending application Ser. No. 383,410, filed June 1, 1982, assigned to the Assignee of this application, disclosed such a discharge spout. In all cases, however, it is essential that the holding tank valve be kept closed during discharge to prevent an awkward and accidental spilling of the tank contents.
The present invention provides structure for automatically locking the valve actuating handle in a "valve closed" position to prevent accidental spilling of the tank contents during carrying and emptying of the tank.
Further advantages accrue in the disclosed preferred embodiment of the invention in which the improved arrangement comprises a rotatably mounted discharge spout on the exterior of the holding tank one end of which fits into an aperture in the top wall of the holding tank and the other end of which is closed by a removable cap.
In order to dump the contents of the holding tank the two toilet sections are separated and the spout is rotated away from its storage position to a position pointing away from the holding tank. The cap is removed, and the tank is tipped so that the waste contents are discharged from the far end of the spout.
In order to promote a smooth flowing discharge which is substantially immune from objectionable characteristics such as belching, a vent valve is provided on the wall of the holding tank for venting the interior head space during dumping. The disclosed embodiment of the vent valve comprises a normally closed spring biased element with an actuator positioned adjacent to a gripping portion of the toilet so that when the toilet is gripped for dumping it is particularly convenient for the person to operate the vent valve actuator concurrent with the grasping and tipping of the holding tank. After the dumping procedure has been completed, the cap is screwed onto the spout, and the spout is returned to its storage position. During dumping, the tank section is conveniently held by the valve actuating handle and the automatic handle locking feature of the invention prevents accidental opening of the valve.
The foregoing features, advantages and benefits of the invention along with additional ones, will be seen in the ensuing description and claims which should be considered in conjunction with the accompanying drawings.